Bourbons3 0 Newbie Poster

My computer has recently been experiencing major problems when starting up.

All connections are right, and everything is plugged in. When i press the power button, the power light goes orange instead of green, and it flashes. The activity light doesnt turn on, when it would normally flash orange.

The computer sounds just as it normally does (with the fan and everything) but does not do that "beep" sound that happens with a regular start up. It just sounds like it's loading something all the time.

The monitor is on, but says no signal input - as if the computer was plugged in, but not switched on.

If anyone can help me, it would be greatly appreciated. Thanks.